Radiation detection device and radiation detection system

Abstract

To maintain the arrangement of multiple sensor units.SOLUTION: The radiation detection device includes a plurality of sensor units, each including a radiation detection section that converts radiation into charge and an integrated circuit that processes signals based on the charge, a support member supporting the integrated circuit of each sensor unit via a first insulating member, a heat dissipation member dissipating heat from the integrated circuits, and a second insulating member positioned between the support member and the heat dissipation member.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to a radiation detection device and a radiation detection system. [Background technology]

[0002] Radiation detection devices have been proposed that have a semiconductor layer that converts radiation into electric charges. In some radiation detection devices, a large sensor surface is formed by arranging multiple sensor units in a one-dimensional or two-dimensional array. The integrated circuit included in the sensor unit generates heat when processing signals based on the electric charges converted by the semiconductor layer. This heat increases the temperature of the semiconductor layer, which may result in noise or a decrease in radiation detection performance. Patent Document 1 describes a structure for dissipating heat generated by the integrated circuit of the sensor unit to a frame. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2020-506375 Summary of the Invention [Problem to be solved by the invention]

[0004] When heat generated in the integrated circuits of the sensor units is dissipated to the frame, the frame may thermally expand. As a result, the arrangement of the multiple sensor units supported by the frame may change, which may result in a deterioration in image quality or damage to the sensor units due to collisions with each other. Some aspects of the present invention aim to provide a technique for maintaining the arrangement of the multiple sensor units. [Means for solving the problem]

[0005] In some embodiments, a radiation detection device is provided, comprising: a plurality of sensor units, each including a radiation detection section that converts radiation into an electric charge and an integrated circuit that processes a signal based on the electric charge; a support member that supports the integrated circuit of each of the plurality of sensor units via a first insulating member; a heat dissipation member that dissipates heat from the integrated circuit; and a second insulating member arranged between the support member and the heat dissipation member. [Effects of the Invention]

[0006] The present disclosure allows for the placement of multiple sensor units to be maintained. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is a block diagram illustrating an example of the configuration of a CT apparatus according to some embodiments. [Figure 2] FIG. 1 is a perspective view illustrating an example of the configuration of a radiation detection apparatus according to some embodiments. [Figure 3] FIG. 1 is a schematic perspective view illustrating an example of the configuration of a sensor module according to some embodiments. [Figure 4] FIG. 1 is a cross-sectional view illustrating an example configuration of a sensor module according to some embodiments. [Figure 5] FIG. 10 is a schematic diagram illustrating an example of an arrangement of sensor units according to some embodiments. [Figure 6] FIG. 1 is a schematic diagram illustrating an example configuration of a radiation detection apparatus according to some embodiments. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the invention claimed. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0009] In the following description, radiation may include α-rays, β-rays, γ-rays, etc., which are beams made of particles (including photons) emitted by radioactive decay, as well as beams having the same or higher energy levels, such as X-rays, particle beams, cosmic rays, etc. In this application, photons such as X-rays and γ-rays and particles such as β-rays and α-rays may be collectively referred to as radiation photons.

[0010] An example configuration of a computed tomography (CT) apparatus 100 according to some embodiments will be described with reference to the block diagram of Fig. 1. The CT apparatus 100 may include a radiation generation unit 101, a wedge 102, a collimator 103, a radiation detection device 104, a tabletop 105, a rotating frame 106, a high-voltage generation unit 107, a data acquisition system (DAS) 108, a signal processing unit 109, a display unit 110, and a control unit 111. This configuration is an example, and the CT apparatus 100 may have other configurations.

[0011] The CT device 100 may be a device capable of performing photon-counting CT. That is, the CT device 100 described in the following embodiments may be a device capable of reconstructing CT image data with a high S / N ratio by counting radiation that has passed through a subject using a photon-counting radiation detection device 104. Furthermore, the radiation detection device 104 described in the following embodiments may be a direct conversion detector that directly converts radiation photons into electric charges proportional to their energy.

[0012] The radiation generating unit 101 irradiates radiation toward the radiation detecting device 104. The radiation generating unit 101 is composed of, for example, a vacuum tube that generates X-rays. A high voltage and a filament current are supplied to the vacuum tube of the radiation generating unit 101 from a high voltage generator 107. X-rays are generated by irradiating the cathode (filament) with thermal electrons toward the anode (target).

[0013] The wedge 102 is a filter that adjusts the amount of radiation 121 irradiated from the radiation generating unit 101. The wedge 102 attenuates the amount of radiation so that the radiation 121 irradiated from the radiation generating unit 101 to the subject 120 has a predetermined distribution. The collimator 103 is made of a lead plate or the like that narrows the irradiation range of the radiation that has passed through the wedge 102. The radiation 121 generated by the radiation generating unit 101 is shaped into a cone beam by the collimator 103 and is irradiated onto the subject 120 on the tabletop 105.

[0014] The radiation detection device 104 detects radiation 121 emitted from the radiation generation unit 101 and passed through the subject 120, and outputs a signal corresponding to the radiation dose to the DAS 108. The subject 120 may be a living thing (e.g., a human or an animal) or an inanimate object.

[0015] The radiation detection device 104 may output a signal capable of measuring the energy value of a radiation photon each time the radiation photon is incident. The radiation photon is, for example, a radiation photon irradiated from the radiation generation unit 101 and transmitted through the subject 120. The radiation detection device 104 has a plurality of detection elements that output one pulse of an electrical signal (analog signal) each time a radiation photon is incident. By counting the number of electrical signals (pulses), it is possible to count the number of radiation photons incident on each detection element. Furthermore, by performing arithmetic processing on this signal, it is possible to measure the energy value of the radiation photon that caused the output of the signal.

[0016] The above-mentioned detection elements may be semiconductor detection elements such as CdTe (cadmium telluride) or CdZnTe (cadmium zinc telluride) with electrodes arranged thereon. In other words, the radiation detection device 104 is a direct conversion detector that directly converts incident radiation photons into electrical signals. The radiation detection device 104 has a plurality of the above-mentioned detection elements and ASICs (Application Specific Integrated Circuits) connected to the detection elements and counting the radiation photons detected by the detection elements. The ASIC counts the number of radiation photons incident on the detection elements by discriminating between the individual charges output by the detection elements. The ASIC also measures the energy of the counted X-ray photons by performing arithmetic processing based on the magnitude of each charge. Furthermore, the ASIC outputs the radiation photon counting result to the DAS 108 as digital data.

[0017] The DAS 108 generates detection data based on the results of the counting process input from the radiation detection device 104. The detection data is, for example, a sinogram. The sinogram is data in which the results of the counting process of radiation incident on each detection element at each position of the radiation generation unit 101 are arranged. The sinogram is data in which the results of the counting process are arranged in a two-dimensional orthogonal coordinate system with the view direction and channel direction as axes. The DAS 108 generates a sinogram, for example, for each row in the slice direction of the radiation detection device 104. The results of the counting process are data in which the number of radiation photons is assigned to each energy bin. For example, the DAS 108 counts photons (radiation photons) derived from radiation irradiated from the radiation generation unit 101 and transmitted through the subject 120, and discriminates the energy of the counted radiation photons to obtain the results of the counting process. The DAS 108 is realized, for example, by a processor.

[0018] The rotating frame 106 is annular and rotatable. Inside the rotating frame 106, the radiation generating unit 101 (wedge 102, collimator 103) and the radiation detecting device 104 are arranged on opposite sides of the top plate 105. The radiation generating unit 101 and the radiation detecting device 104 are rotatable together with the rotating frame 106.

[0019] The high-voltage generator 107 includes a boost circuit and outputs a high voltage to the radiation generation unit 101. For example, the high-voltage generator 107 has electrical circuits such as a transformer and a rectifier, and includes a high-voltage generation unit that generates a high voltage to be applied to the radiation generation unit 101, and a radiation control unit that controls the output voltage according to the radiation generated by the radiation generation unit 101. The high-voltage generation unit may be a transformer type or an inverter type. The high-voltage generator 107 may be provided on the rotating frame 106, or on a fixed frame (not shown). The DAS 108 includes an amplifier circuit and an analog-to-digital (A / D) conversion circuit, and outputs a signal from the radiation detection device 104 to the signal processing unit 109 as digital data.

[0020] The signal processing unit 109 processes signals output from the radiation detection device 104. The signal processing unit 109 may include a central processing unit (CPU), a read-only memory (ROM), and a random access memory (RAM). The display unit 110 includes a flat display device or the like and is capable of displaying radiation images. The control unit 111 includes a CPU, a ROM, a RAM, and the like and controls the overall operation of the CT device 100. For example, the control unit 111 includes a processing circuit having a CPU or the like and a driving mechanism such as a motor and an actuator. The control unit 111 receives input signals from the input interface and controls the operation of the gantry device and the bed device. For example, the control unit 111 controls the rotation of the rotating frame 106, the tilt of the gantry device, the operation of the bed device and the tabletop, etc. For example, to control the tilt of the gantry device, the control unit 111 rotates the rotating frame 106 around an axis parallel to the X-axis direction based on input inclination angle (tilt angle) information. The control unit 111 may be provided in the gantry device or in the console device.

[0021] The input interface accepts various input operations from the operator, converts the accepted input operations into electrical signals, and outputs the electrical signals to the control unit 111. For example, the input interface accepts input operations from the operator, such as reconstruction conditions for reconstructing CT image data and image processing conditions for generating post-processing images from the CT image data. For example, the input interface may be implemented by a mouse, keyboard, trackball, switch, button, joystick, touchpad for performing input operations by touching the operation surface, a touchscreen in which the display screen and touchpad are integrated, a non-contact input circuit using an optical sensor, a voice input circuit, or the like. The input interface may be provided on the gantry device. The input interface may also be configured as a tablet terminal or the like capable of wireless communication with the console device itself. The input interface is not limited to those having physical operating components such as a mouse and keyboard. For example, an electrical signal processing circuit that receives an electrical signal corresponding to an input operation from an external input device provided separately from the console device and outputs the electrical signal to the control unit 111 is also included as an example of an input interface.

[0022] The signal processing unit 109 may have a preprocessing function. By using the preprocessing function, the signal processing unit 109 can generate projection data by performing preprocessing such as logarithmic conversion processing, offset correction processing, inter-channel sensitivity correction processing, and beam hardening correction on the detection data output from the DAS 108. The signal processing unit 109 may also have a reconstruction processing function. By using the reconstruction processing function, the signal processing unit 109 can generate CT image data by performing reconstruction processing using a filtered back projection method, an iterative reconstruction method, or the like on the projection data generated by the preprocessing function. By using the reconstruction processing function, the signal processing unit 109 can store the reconstructed CT image data in a memory.

[0023] The projection data generated from the counting results obtained by photon-counting CT includes information on the energy of X-rays attenuated by passing through the subject 120. Therefore, the signal processing unit 109 can reconstruct, for example, CT image data of a specific energy component using its reconstruction processing function. The signal processing unit 109 can also reconstruct, for example, CT image data for each of a plurality of energy components using its reconstruction processing function. The signal processing unit 109 can also assign, for example, a color tone corresponding to the energy component to each pixel of the CT image data for each energy component, and generate image data in which a plurality of CT image data color-coded according to the energy component are superimposed using its reconstruction processing function. The signal processing unit 109 can also generate image data that enables identification of a substance using, for example, the K-absorption edge specific to the substance using its reconstruction processing function. Examples of other image data generated by the signal processing unit 109 using its reconstruction processing function include monochromatic X-ray image data, density image data, and effective atomic number image data.

[0024] To reconstruct CT image data, projection data for 360° around the subject is required, and even with the half-scan method, projection data for 180° + fan angle is required. Either reconstruction method is applicable to this embodiment. For simplicity of explanation, the following will use a reconstruction method (full-scan reconstruction) that uses projection data for 360° around the subject.

[0025] The signal processing unit 109 may have an image processing function. The image processing function allows the signal processing unit 109 to convert CT image data generated by the reconstruction processing function into image data such as a tomographic image of an arbitrary cross section or a three-dimensional image obtained by rendering processing, using a known method, based on an input operation received from an operator via an input interface. The signal processing unit 109 can also store the converted image data in memory using the image processing function.

[0026] The control unit 111 may have a scan control function. The control unit 111 controls the CT scan performed by the gantry device using the scan control function. For example, the control unit 111 controls the operation of the high-voltage generator 107, the radiation detection device 104, the DAS 108, and the bed driving device using the scan control function, thereby controlling the collection process of counting results in the gantry device. As an example, the control unit 111 uses the scan control function to control the collection process of projection data in imaging to collect positioning images (scanograms) and in actual imaging (scan) to collect images used for diagnosis. The control unit 111 may also have a display control function. Using the display control function, the control unit 111 can control various image data stored in the memory to be displayed on the display unit 110, such as a display.

[0027] An example configuration of the radiation detection device 104 will be described with reference to the perspective view of Fig. 2. This configuration is one example, and the radiation detection device 104 may have other configurations. The radiation detection device 104 includes a base 201 and a plurality of sensor modules 202. The base 201 has an arc shape that is concave with respect to the radiation 121. The plurality of sensor modules 202 are fixed to the curved surface of the base 201 in a line along the circumferential direction. The base 201 is fixed to a rotating frame 106.

[0028] An example configuration of the sensor module 202 will be described with reference to the perspective view of FIG. 3. This configuration is an example, and the sensor module 202 may have other configurations. Each of the multiple sensor modules 202 included in the radiation detection device 104 may have the configuration described in FIG. 3. The sensor module 202 may include multiple sensor units 301a to 301d, a heat dissipation member 302, a frame 303, and a circuit board 304. In the following description, the multiple sensor units 301a to 301d will be collectively referred to as sensor unit 301. The description of the sensor unit 301 may also apply to each of the multiple sensor units 301a to 301d.

[0029] The sensor unit 301 generates a signal corresponding to radiation incident on the sensor unit 301. The sensor unit 301 and the circuit board 304 are connected by a cable (not shown, for example, a flexible cable). The signal generated by the sensor unit 301 is read out to the DAS 108 through the circuit board 304. The multiple sensor units 301 are arranged side by side in the direction in which the frame 303 extends. In the example of FIG. 3, one sensor module 202 includes four sensor units 301, but the number of sensor units is not limited to this example. Furthermore, in the example of FIG. 3, the four sensor units 301 are arranged in a single row, but the multiple sensor units may be arranged in multiple rows.

[0030] The frame 303 is a rigid member for mounting the sensor unit 301. The frame 303 may be called a mount frame. The frame 303 functions as a support member for supporting the sensor unit 301. A circuit board 304 is attached to the frame 303. The multiple sensor units 301 and the circuit board 304 are located on opposite sides of the frame 303. The frame 303 is fixed to the base 201. For example, the frame 303 may be mechanically fixed to the base 201 using fasteners such as screws, or chemically fixed to the base 201 using an adhesive.

[0031] The heat dissipation member 302 is located between the frame 303 and the lower surface of each of the plurality of sensor units 301a to 301d. One heat dissipation member 302 may be disposed in common for the plurality of sensor units 301. Alternatively, an individual heat dissipation member 302 may be disposed for each of the plurality of sensor units 301. The heat dissipation member 302 dissipates heat from the sensor unit 301 (specifically, the integrated circuit 406 described below).

[0032] A more specific configuration example of the sensor module 202 will be described with reference to Fig. 4. Fig. 4(a) and Fig. 4(b) show cross-sectional views of two configuration examples of the sensor module 202. Unless otherwise stated, the following description applies to both the configuration examples of Fig. 4(a) and Fig. 4(b). The sensor module 202 may have a configuration that is not shown in Fig. 4.

[0033] The sensor unit 301 may include a semiconductor layer 402, an interposer 404, and an integrated circuit 406. In the following description, the upper surface of each component in the drawing will be referred to as the upper surface, and the lower surface of each component in the drawing will be referred to as the lower surface. The sensor unit 301 has the upper surface 401 located on the radiation incident side and the lower surface 407 located on the opposite side to the upper surface 401. FIG. 4 shows only two adjacent sensor units 301 in the array out of the multiple sensor units 301 included in the sensor module 202. Any two adjacent sensor units 301 out of the multiple sensor units 301 included in the sensor module 202 may have the configuration shown in FIG. 4.

[0034] The semiconductor layer 402 functions as a radiation detection section that converts radiation into electric charges. An upper surface 401 of the semiconductor layer 402 is located on the incident side of the radiation 121. In the example of FIG. 4, the semiconductor layer 402 is located at the top of the sensor unit 301 (the position farthest from the frame 303). Therefore, the upper surface of the semiconductor layer 402 forms the upper surface 401 of the sensor unit 301.

[0035] The semiconductor layer 402 may be a single crystal substrate of a semiconductor that converts radiation directly into an electric charge, such as cadmium zinc telluride (CdZnTe) or cadmium telluride (CdTe), or a single crystal substrate of a semiconductor such as silicon (Si), lead iodide (PbI), mercury iodide (HgI), bismuth iodide (BiI), or thallium bromide (TlBr).

[0036] The electrodes formed on the lower surface of the semiconductor layer 402 and the electrodes formed on the upper surface of the interposer 404 are electrically and physically connected to each other by bumps 403. Individual electrodes corresponding to the pixels of the sensor unit 301 are formed on the lower surface of the semiconductor layer 402. The electrodes formed on the lower surface of the interposer 404 and the electrodes formed on the upper surface of the integrated circuit 406 are electrically and physically connected to each other by bumps 405. The bumps 403 and 405 are formed of, for example, solder. An anisotropic conductive film (ACF) may be used instead of the bumps 403 and 405. The interposer 404 relays signals between the semiconductor layer 402 and the integrated circuit 406. That is, the interposer 404 and the bumps 403 and 405 form a connection layer that connects the semiconductor layer 402 and the integrated circuit 406. The interposer 404 may be omitted. In this case, the electrode formed on the lower surface of the semiconductor layer 402 and the electrode formed on the upper surface of the integrated circuit 406 may be electrically and physically connected to each other by a bump or the like.

[0037] The integrated circuit 406 may be an energy-resolving counter circuit (ERCE). For example, the integrated circuit 406 may have a function of counting electrical pulses generated by radiation photons incident on the semiconductor layer 402. Alternatively, the integrated circuit 406 may read out a voltage corresponding to the charge accumulated in the semiconductor layer 402 from the semiconductor layer 402. In this manner, the integrated circuit 406 has a function of processing a signal based on the charge converted by the radiation from the semiconductor layer 402. In the example of FIG. 4, the integrated circuit 406 is located at the bottom of the sensor unit 301 (the position closest to the frame 303). Therefore, the bottom surface of the integrated circuit 406 forms the bottom surface 407 of the sensor unit 301.

[0038] The sensor module 202 further includes a heat insulating member 408. The heat insulating member 408 is an example of a first heat insulating member. The frame 303 supports the integrated circuits 406 of each of the multiple sensor units 301 via the heat insulating member 408. In this manner, the frame 303 functions as a support member. The upper surface of the heat insulating member 408 may be coupled to the lower surface of the frame 303. For example, the heat insulating member 408 may be mechanically fixed to the integrated circuit 406 using a fastener such as a screw, or may be chemically fixed to the integrated circuit 406 using an adhesive, double-sided tape, or the like. The heat insulating member 408 and the integrated circuit 406 may be in contact with each other, or another member may be interposed between the heat insulating member 408 and the integrated circuit 406.

[0039] The upper surface of frame 303 may be bonded to the lower surface of heat insulating member 408. For example, frame 303 may be mechanically fixed to integrated circuit 406 using fasteners such as screws, or may be chemically fixed to integrated circuit 406 using adhesive, double-sided tape, or the like. Frame 303 and integrated circuit 406 may be in contact with each other, or another member may be interposed between frame 303 and integrated circuit 406.

[0040] The heat insulating member 408 may include multiple portions separated for each integrated circuit 406. In this case, each portion of the heat insulating member 408 is disposed between one integrated circuit 406 and the frame 303. Alternatively, the heat insulating member 408 may be disposed across two or more integrated circuits 406. In this case, one portion of the heat insulating member 408 is disposed between one integrated circuit 406 and the frame 303, and another portion of the heat insulating member 408 is disposed between another integrated circuit 406 and the frame 303.

[0041] The heat insulating member 408 is made of a material with a relatively low thermal conductivity, such as a resin or foam material. Specifically, the heat insulating member may be a member having a thermal conductivity of less than 1 W / (m·K). For example, the heat insulating member 408 may have a thermal conductivity of approximately 0.02 to 0.6 W / (m·K).

[0042] By disposing the heat insulating member 408 between the frame 303 and the integrated circuit 406, the heat generated in the integrated circuit 406 is prevented from being transferred to the frame 303. This makes it possible to select the material of the frame 303 without considering thermal expansion. For example, the frame 303 may be formed of a material with relatively high rigidity, such as a metal such as aluminum or stainless steel.

[0043] The heat dissipation member 302 dissipates heat from the integrated circuit 406. The heat dissipation member 302 may be in contact with the integrated circuit 406. Alternatively, as shown in FIG. 4 , the sensor module 202 may further include a thermally conductive member 409 between the heat dissipation member 302 and the integrated circuit 406. The thermally conductive member 409 is in contact with both the heat dissipation member 302 and the integrated circuit 406, and transfers heat from the integrated circuit 406 to the heat dissipation member 302.

[0044] Heat conducting member 409 may have a relatively high thermal conductivity to efficiently transfer heat. For example, heat conducting member 409 may have a thermal conductivity higher than that of heat insulating member 408. Specifically, heat conducting member 409 may have a thermal conductivity of about 1 to 30 W / (m·K), or even about 1.5 to 20 W / (m·K).

[0045] Furthermore, the heat conduction member 409 may have a relatively high degree of elasticity in order to efficiently transfer heat. For example, the heat conduction member 409 may have a higher degree of elasticity than the heat dissipation member 302. When the heat conduction member 409 has such elasticity, the heat dissipation member 302 and the integrated circuit 406 are in closer contact with each other than when the heat dissipation member 302 and the integrated circuit 406 are in contact with each other, thereby improving the heat dissipation performance of the integrated circuit 406 by the heat dissipation member 302.

[0046] To have the above-mentioned properties, heat dissipating rubber or heat conductive grease may be used as the material for heat conducting member 409. Heat dissipating rubber is rubber with excellent heat dissipation properties, and may be rubber with a thermal conductivity of, for example, about 1 to 30 W / (m·K), or even about 1.5 to 20 W / (m·K).

[0047] The heat dissipation member 302 may have a relatively high thermal conductivity. For example, the heat conduction member 409 may have a higher thermal conductivity than the heat insulation member 408, or may have a higher thermal conductivity than the heat conduction member 409. Specifically, the heat dissipation member 302 may have a thermal conductivity of 100 W / (m·K) or more. For example, the heat insulation member 408 may be formed of a metal such as aluminum (thermal conductivity: approximately 222 W / (m·K)), copper (thermal conductivity: approximately 393 W / (m·K)), iron (thermal conductivity: approximately 73.3 W / (m·K)), or stainless steel (thermal conductivity: approximately 16 to 25 W / (m·K)). Because the heat conduction member 409 has a relatively high elasticity, even if the heat dissipation member 302 thermally expands, the load applied to the integrated circuit 406 can be reduced, and fluctuations in the placement of the sensor unit 301 can be suppressed. Therefore, the material of the heat dissipation member 302 can be selected without taking thermal expansion into consideration.

[0048] The heat dissipation member 302 may be separate for each integrated circuit 406, or may be shared by two or more integrated circuits 406. Furthermore, a plurality of heat dissipation members 302 may be arranged for one integrated circuit 406. When the heat dissipation member 302 is shared by two or more integrated circuits 406, a hole for passing the heat insulating member 408 may be formed in the heat dissipation member 302.

[0049] The sensor module 202 may further include a heat insulating member 410 disposed between the frame 303 and the heat dissipation member 302. The heat insulating member 410 is an example of a second heat insulating member. The frame 303 may support the heat dissipation member 302 via the heat insulating member 410. Since the frame 303 and the heat dissipation member 302 are insulated from each other, the heat transferred from the heat dissipation member 302 to the frame 303 can be reduced.

[0050] The heat insulating member 410 is formed of a material with relatively low thermal conductivity and relatively high elasticity, such as rubber or foam. For example, the heat insulating member 410 may have a thermal conductivity of less than 1 W / (m·K), or may have a thermal conductivity of approximately 0.02 to 0.6 W / (m·K). The heat insulating member 410 may have a thermal conductivity lower than that of the heat dissipation member 302. The heat insulating member 410 may have greater elasticity than the heat dissipation member 302. As a result, even if the heat dissipation member 302 thermally expands, this expansion can be absorbed by the expansion and contraction of the heat insulating member 410, thereby reducing the load applied to the frame 303.

[0051] The sensor module 202 may not include the heat insulating member 410. In this case, the frame 303 and the heat dissipation member 302 may be disposed with a gap therebetween, and the frame 303 and the heat dissipation member 302 may be insulated from each other by an air layer. Furthermore, instead of or in addition to the heat insulating member 410, a part of the heat insulating member 408 may be disposed between the frame 303 and the heat dissipation member 302.

[0052] The integrated circuit 406 and the heat conductive member 409 may simply be in contact with each other, or may not be bonded to each other. The heat conductive member 409 and the heat dissipation member 302 may simply be in contact with each other, or may not be bonded to each other. The heat dissipation member 302 and the heat insulating member 410 may be bonded to each other, or may not be bonded to each other. The heat insulating member 410 and the frame 303 may be bonded to each other, or may not be bonded to each other.

[0053] In the configuration example of FIG. 4( a), the integrated circuit 406 dissipates heat to the heat dissipation member 302 from the underside of the integrated circuit 406, i.e., the surface supported by the frame 303. When the amount of heat generated from the underside of the integrated circuit 406 is greater than the amount of heat generated from the side surfaces of the integrated circuit 406, such a configuration allows the integrated circuit 406 to effectively dissipate heat. When the underside of the integrated circuit 406 has a distribution of heat generation amounts, the heat dissipation member 302 may dissipate heat from the portion of the underside of the integrated circuit 406 where the amount of heat generation is high. A high amount of heat generation may mean a value higher than the average of the distribution of heat generation amounts. Specifically, the thermal conductive member 409 may be in contact with the portion of the underside of the integrated circuit 406 where the amount of heat generation is high.

[0054] The area of ​​the portion of the underside of the integrated circuit 406 supported by the frame 303 may be larger than the area of ​​the portion of the underside of the integrated circuit 406 used for heat dissipation to the heat dissipation member 302. In the example of FIG. 4( a), the portion of the underside of the integrated circuit 406 supported by the frame 303 refers to the portion of the underside of the integrated circuit 406 that comes into contact with the heat insulating member 408. When another member is interposed between the heat insulating member 408 and the integrated circuit 406, the portion of the underside of the integrated circuit 406 supported by the frame 303 refers to the portion of the underside of the integrated circuit 406 that comes into contact with this other member. In the example of FIG. 4( a), the portion of the underside of the integrated circuit 406 used for heat dissipation to the heat dissipation member 302 refers to the portion of the underside of the integrated circuit 406 that comes into contact with the heat conductive member 409. When the heat conductive member 409 is not included, the portion of the underside of the integrated circuit 406 used for heat dissipation to the heat dissipation member 302 refers to the portion of the underside of the integrated circuit 406 that comes into contact with the heat dissipation member 302. By having the frame 303 support the integrated circuit 406 over such a large area, the frame 303 can stably support the integrated circuit 406.

[0055] 4(b), the integrated circuit 406 dissipates heat to the heat dissipation member 302 from a side surface of the integrated circuit 406, i.e., a surface different from the surface supported by the frame 303. The contact area between the integrated circuit 406 and the heat insulating member 408 can be increased, allowing the frame 303 to stably support the integrated circuit 406. Furthermore, compared to the configuration example of FIG. 4(a), the distance between the sensor unit 301 and the frame 303 can be reduced, allowing the thickness of the sensor module 202 and the radiation detection device 104 to be reduced.

[0056] In the sensor module 202 having the above-described configuration, the heat generated in the integrated circuit 406 can be prevented from being transferred to the frame 303, and therefore the arrangement of the plurality of sensor units 301 can be maintained.

[0057] In the above-described embodiment, the radiation detection device 104 is described in the context of the CT device 100. The CT device 100 is an example of a radiation detection system including the radiation detection device 104 and a signal processing unit 109 that processes signals output from the radiation detection device 104. The radiation detection device 104 may be used in devices other than the CT device 100, such as a fluoroscopic diagnostic device or an article inspection device. In addition, in the above-described embodiment, the radiation detection device 104 that detects radiation has been described. However, the embodiment is not limited to this, and the above-described embodiment can also be applied to a radiation detector that detects gamma rays, particle radiation, etc. In addition to the CT device 100, the above-described embodiment can also be applied to a radiation diagnostic device equipped with the radiation detection device 104. In such a case, the radiation diagnostic device includes, for example, a PET (Positron Emission Tomography) device, a SPECT (Single Photon Emission Computed Tomography) device, etc.

[0058] A modified example of the above-described radiation detection device 104 will be described with reference to Fig. 5. In the radiation detection device 104 used in the CT device 100, the upper surfaces of the semiconductor layers 402 of the multiple sensor units 301 (i.e., the incident surfaces onto which radiation is incident) are arranged along a curved surface. Alternatively, the upper surfaces of the semiconductor layers 402 of the multiple sensor units 301 (i.e., the incident surfaces onto which radiation is incident) may be arranged along a flat surface, as shown in each diagram of Fig. 5.

[0059] For ease of viewing, each diagram in FIG. 5 shows only a sensor unit 301, a frame 303, and a circuit board 304. In FIG. 5(a), a plurality of sensor units 301 are arranged to form a 6×6 two-dimensional array. One frame 303 and one circuit board 304 are arranged in common for these plurality of sensor units 301. In FIG. 5(b), a plurality of sensor units 301 are arranged to form a 6×2 two-dimensional array. In FIG. 5(c), a plurality of sensor units 301 are arranged to form a 6×1 one-dimensional array. In FIG. 5(d), one sensor unit 301 is arranged.

[0060] Referring to Fig. 6, a configuration example of a radiation detection device 600 in which the upper surfaces of the semiconductor layers 402 of multiple sensor units 301 are arranged along a plane will be described. The radiation detection device 600 may be, for example, a flat panel detector (FPD). Fig. 6(a) shows a cross-sectional view of the radiation detection device 600, and Fig. 6(b) shows a plan view of the radiation detection device 600 as seen from the radiation incident side. In Fig. 6(b), for the sake of explanation, a housing 601 is shown transparently.

[0061] Similar to the radiation detection device 104 described above, the radiation detection device 600 may include a plurality of sensor units 301, a heat dissipation member 302, a frame 303, a heat insulating member 408, a heat conduction member 409, and a heat insulating member 410. These components may have the same configuration as the radiation detection device 104. In FIG. 6(a), these components have the same configuration as in FIG. 4(a). Alternatively, these components may have the same configuration as in FIG. 4(b). In the example of FIG. 6, the radiation detection device 600 includes four sensor units 301 arranged in a 2×2 pattern. Alternatively, the radiation detection device 600 may include other numbers and arrangements of sensor units 301.

[0062] The radiation detection device 600 may further include a housing 601, a circuit board 603, a heat-conducting member 604, and a cooling unit 605. The radiation detection device 600 may not include at least one of these components.

[0063] The housing 601 houses the components of the radiation detection device 600, including the multiple sensor units 301, the heat dissipation member 302, the frame 303, the heat insulating member 408, the heat conductive member 409, and the heat insulating member 410. The housing 601 can protect the housed components from external forces. The housing 601 may also protect the sensor units 301 and the circuit board 603 from electromagnetic waves generated outside the radiation detection device 600, thereby suppressing deterioration in the image quality of radiographic images and stabilizing the operation of the radiation detection device 600. The housing 601 may be made of a material that has relatively high rigidity and conductivity, such as aluminum, stainless steel, or carbon fiber reinforced plastic (CFRP).

[0064] The housing 601 has an incident surface 602. The incident surface 602 may be the surface of the radiation detection device 600 onto which radiation 121 is incident when the radiation detection device 600 is in use. The incident surface 602 may be formed of a material different from that of other areas of the housing 601. The sensor unit 301 is arranged so that its top surface 401 is located on the incident surface 602 side.

[0065] The frame 303 is supported by a housing 601. The radiation detection device 600 may further include a circuit board 603. Circuit elements for processing signals output from the sensor units 301 and for controlling the sensor units 301 are mounted on the circuit board 603. The circuit board 603 may be supported by the frame 303. The circuit board 603 is arranged on the opposite side of the frame 303 to the multiple sensor units 301. The sensor units 301 and the circuit board 603 are electrically connected by cables, connectors, bumps, etc.

[0066] The heat dissipation member 302 extends to the outside of the plurality of sensor units 301 in a plan view with respect to the incident surface 602 (i.e., FIG. 6(b)). By using such a large heat dissipation member 302, the heat of the integrated circuit 406 can be dissipated effectively.

[0067] The heat of the heat dissipation member 302 may be transferred to the housing 601. Specifically, the heat dissipation member 302 may be in contact with the housing 601. Alternatively, as shown in FIG. 6 , the radiation detection device 600 may further include a heat conduction member 604 between the housing 601 and the heat dissipation member 302. The heat conduction member 604 is in contact with both the housing 601 and the heat dissipation member 302, and transfers the heat of the heat dissipation member 302 to the housing 601.

[0068] The heat conducting member 604 may have a relatively high thermal conductivity to efficiently transfer heat. For example, the heat conducting member 604 may have a thermal conductivity higher than that of the heat insulating member 408. Specifically, the heat conducting member 604 may have a thermal conductivity of about 1 to 30 W / (m·K), or even about 1.5 to 20 W / (m·K).

[0069] Furthermore, the heat conduction member 604 may have relatively high elasticity to efficiently transfer heat. For example, the heat conduction member 604 may have greater elasticity than the heat dissipation member 302. When the heat conduction member 604 has such elasticity, the housing 601 and the heat dissipation member 302 are in closer contact with each other than when they are in contact with each other, thereby improving the heat dissipation performance of the heat dissipation member 302 by the housing 601. To achieve the above-described properties, heat dissipation rubber or heat conductive grease may be used as the material for the heat conduction member 604. The heat transferred to the housing 601 is dissipated to the outside of the radiation detection device 600. In the example of FIG. 6, the heat is dissipated from the heat dissipation member 302 to two inner walls of the housing 601. Alternatively, the heat may be dissipated from the heat dissipation member 302 to one or three or more inner walls of the housing 601.

[0070] The heat dissipation member 302 may have a radiation shielding function. For example, the radiation transmittance of the heat dissipation member 302 may be 10% or less. Specifically, the heat dissipation member 302 may have a thickness that provides a radiation transmittance of 10% or less. The radiation transmittance may be the ratio of the intensity of radiation that has passed through the heat dissipation member 302 to the intensity of radiation that has entered the heat dissipation member 302 from the incident surface 602 side. The wavelength of radiation used to measure the radiation transmittance may be the wavelength that is the target of detection by the sensor unit 301. In this way, the heat dissipation member 302 has a radiation shielding function, which can reduce the radiation that reaches the circuit board 603, thereby stabilizing the operation of the circuit elements of the circuit board 603.

[0071] The radiation detection device 600 may further include a cooling unit 605 that cools the heat dissipation member 302. The cooling unit 605 may be, for example, a heat sink such as fins, an air-cooling fan, a water-cooled plate, a Peltier element, or the like. In the example of Fig. 6, the cooling unit 605 is attached to the heat dissipation member 302. Alternatively, the cooling unit 605 may be attached to another component, for example, the housing 601. The cooling unit 605 allows the integrated circuit 406 to dissipate heat more effectively.

[0072] The above description of the radiation detection apparatus 600 may also be applied to the radiation detection apparatus 104. For example, the radiation detection apparatus 104 may further include a cooling unit 605 that cools the heat dissipation member 302.

[0073] <Summary of the embodiment> [Item 1] A radiation detection device, comprising: a plurality of sensor units each including a radiation detection unit that converts radiation into electric charges and an integrated circuit that processes signals based on the electric charges; a support member that supports the integrated circuits of each of the plurality of sensor units via a first heat insulating member; a heat dissipation member that dissipates heat from the integrated circuit; a second heat insulating member disposed between the support member and the heat dissipation member. [Item 2] the radiation detection device further includes a thermally conductive member between the integrated circuit and the heat dissipation member; the heat conduction member transfers heat from the integrated circuit to the heat dissipation member; Item 2. The radiation detection device according to item 1, wherein the heat conducting member has higher elasticity than the heat dissipating member. [Item 3] 3. The radiation detection device according to claim 1, wherein the integrated circuit dissipates heat to the heat dissipation member from a surface supported by the support member. [Item 4] 4. The radiation detection device according to item 3, wherein the area of ​​the portion of the surface of the integrated circuit that is supported by the support member is larger than the area of ​​the portion of the surface of the integrated circuit that is used for heat dissipation to the heat dissipation member. [Item 5] 3. The radiation detection device according to claim 1, wherein the integrated circuit dissipates heat to the heat dissipation member from a surface different from a surface supported by the support member. [Item 6] 6. The radiation detection device according to any one of items 1 to 5, wherein the heat dissipation member extends to the outside of the plurality of sensor units in a plan view of the radiation detection device with respect to a surface on which radiation is incident. [Item 7] 7. The radiation detection device according to item 6, wherein the radiation transmittance of the heat dissipation member is 10% or less. [Item 8] 8. The radiation detection device according to any one of items 1 to 7, further comprising a cooling unit that cools the heat dissipation member. [Item 9] the radiation detection device further includes a housing that accommodates the plurality of sensor units, the support member, the heat dissipation member, the first heat insulating member, and the second heat insulating member; 9. The radiation detection device according to any one of items 1 to 8, wherein heat is transferred from the heat dissipation member to the housing. [Item 10] the radiation detection device further includes a second heat conduction member between the housing and the heat dissipation member; Item 10. The radiation detection device according to item 9, wherein the second heat conducting member has higher elasticity than the heat dissipating member. [Item 11] Item 11. The radiation detection device according to item 9 or 10, wherein the support member is supported by the housing. [Item 12] the radiation detection device further includes a circuit board supported by the support member; the circuit board is disposed on the opposite side of the support member from the plurality of sensor units, 12. The radiation detection device according to any one of claims 1 to 11, wherein the circuit board is configured to control the plurality of sensor units. [Item 13] 13. The radiation detection device according to any one of items 1 to 12, wherein the incident surfaces of the radiation detection sections of the plurality of sensor units are arranged along a curved surface. [Item 14] 13. The radiation detection device according to any one of items 1 to 12, wherein the incident surfaces of the radiation detection sections of the plurality of sensor units are arranged along a plane. [Item 15] A radiation detection device, comprising: a plurality of sensor units each including a radiation detection unit that converts radiation into electric charges and an integrated circuit that processes signals based on the electric charges; a support member that supports the integrated circuits of each of the plurality of sensor units via a first heat insulating member; a heat dissipation member that dissipates heat from the integrated circuit, The radiation detection device, wherein the support member and the heat dissipation member are thermally insulated from each other. [Item 16] A radiation detection device according to any one of items 1 to 15, a signal processing unit that processes a signal output from the radiation detection device, the radiation detection device is a photon-counting radiation detection device, The signal processing unit generates image data using a count result of radiation photons derived from radiation that has passed through the subject.

[0074] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0075] 100 CT device, 104 radiation detection device, 301 sensor unit, 302 heat dissipation member, 303 frame

Claims

1. A radiation detection device, comprising: a plurality of sensor units each including a radiation detection unit that converts radiation into electric charges and an integrated circuit that processes signals based on the electric charges; a support member that supports the integrated circuits of each of the plurality of sensor units via a first heat insulating member; a heat dissipation member that dissipates heat from the integrated circuit; a second heat insulating member disposed between the support member and the heat dissipation member.

2. the radiation detection device further includes a thermally conductive member between the integrated circuit and the heat dissipation member; the heat conduction member transfers heat from the integrated circuit to the heat dissipation member; The radiation detection device according to claim 1 , wherein the heat conducting member has higher flexibility than the heat dissipating member.

3. The radiation detection device according to claim 1 , wherein the integrated circuit radiates heat to the heat radiating member from a surface supported by the support member.

4. 4. The radiation detection device according to claim 3, wherein an area of ​​a portion of the surface of the integrated circuit supported by the support member is larger than an area of ​​a portion of the surface of the integrated circuit used for heat dissipation to the heat dissipation member.

5. The radiation detection device according to claim 1 , wherein the integrated circuit radiates heat to the heat radiating member from a surface different from a surface supported by the support member.

6. The radiation detection device according to claim 1 , wherein the heat dissipation member extends to an outside of the plurality of sensor units in a plan view of the radiation detection device with respect to a surface on which radiation is incident.

7. The radiation detection device according to claim 6 , wherein the radiation transmittance of the heat dissipation member is 10% or less.

8. The radiation detection apparatus according to claim 1 , further comprising a cooling unit that cools the heat dissipation member.

9. the radiation detection apparatus further includes a housing that accommodates the plurality of sensor units, the support member, the heat dissipation member, the first heat insulating member, and the second heat insulating member; The radiation detection device according to claim 1 , wherein heat is transferred from the heat dissipation member to the housing.

10. the radiation detection device further includes a second heat conduction member between the housing and the heat dissipation member; The radiation detection device according to claim 9 , wherein the second heat conducting member has higher flexibility than the heat dissipating member.

11. The radiation detection device according to claim 9 , wherein the support member is supported by the housing.

12. the radiation detection device further includes a circuit board supported by the support member; the circuit board is disposed on the opposite side of the support member from the plurality of sensor units, The radiation detection device of claim 1 , wherein the circuit board is configured to control the plurality of sensor units.

13. The radiation detection device according to claim 1 , wherein the incident surfaces of the radiation detection sections of the plurality of sensor units are arranged along a curved surface.

14. The radiation detection device according to claim 1 , wherein the incident surfaces of the radiation detection sections of the plurality of sensor units are arranged along a plane.

15. A radiation detection device, comprising: a plurality of sensor units each including a radiation detection unit that converts radiation into electric charges and an integrated circuit that processes signals based on the electric charges; a support member that supports the integrated circuits of each of the plurality of sensor units via a first heat insulating member; a heat dissipation member that dissipates heat from the integrated circuit, The radiation detection device, wherein the support member and the heat dissipation member are thermally insulated from each other.

16. A radiation detection device according to any one of claims 1 to 15; a signal processing unit that processes a signal output from the radiation detection device, the radiation detection device is a photon-counting radiation detection device, The signal processing unit generates image data using a count result of radiation photons derived from radiation that has passed through the subject.

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